Conventionally, in image forming apparatus such as a copier, a printer and the like, power is supplied to a variety of devices such as a fixer, an image exposure device which uses a laser beam, charger and discharger, an image bearer belt, and a driving motor of an image bearer body such as a photoconductive drum, etc., from a power source unit.
The power source unit typically includes an AC filter unit and an insulated DC output circuit unit. Power is inputted to the AC filter of the power source unit from an external AC power source which is a commercial power source. The AC filter unit and the DC output circuit unit are coupled to each other via an electrical wiring. By such a configuration, the power source unit supplies DC power to various devices.
In the power source unit, a power source unit of one type generally is applied to several models; however, a main body of the image forming apparatus recently requires much power due to increasing of a copy speed (the number of print per unit time), colorization, energy consumption save such as a sleep mode and the like.
Thereby, measures such as lowering of a copy speed and a temporary stop of copying operation are proposed when power is not sufficiently supplied to the image forming apparatus, but the image forming apparatus cannot show a complete performance by such measures.
Meanwhile, it is known to prevent power shortage in the power source unit by improving harmonics (harmonic interference occurring in electrical wirings) of AC filter unit and a power factor, and, a reactor is used for this.
However, since power can sufficiently and stably be supplied depending on models of the image forming apparatus although the power source unit is not provided with the reactor having a weight, the reactor is optionally provided to the power source unit of models requiring it, which can reduce cost and make the image forming apparatus light-weighted.
In addition, if shipping the image forming apparatus in a state of the weighted reactor being attached to the AC filter unit or the DC output circuit unit, a frame of the apparatus main body equipped with the reactor is in danger of being influenced by transporting a package containing the image forming apparatus, opening the package and carrying the image forming apparatus to a place for installment and so forth at the time of shipping from a factory.
Further, the reactor emits heat and thus needs to be cooled, however, providing a cooling device dedicated to the reactor causes increase of cost and weight as well as requires a margin for displacement space of the cooling device to make it difficult to layout the members configuring the power source unit.